DS1621

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COMMAND SET

Data and control information is read from and written to the DS1621 in the format shown in Figure 5. To

“0”. After receiving an acknowledge, the bus master provides a command protocol. After receiving this

protocol, the DS1621 will issue an acknowledge and then the master may send data to the DS1621. If the

DS1621 is to be read, the master must send the command protocol as before and then issue a repeated

data from the DS1621. The command set for the DS1621 as shown in Table 3 is as follows:

Read Temperature [AAh]

This command reads the last temperature conversion result. The DS1621 will send 2 bytes, in the format

described earlier, which are the contents of this register.

Access TH [A1h]

command, the next 2 bytes written to the DS1621, in the same format as described for reading

value stored in this register is read back.

Access TL [A2h]

command, the next 2 bytes written to the DS1621, in the same format as described for reading

value stored in this register is read back.

Access Config [ACh]

the value stored in the configuration register.

Read Counter [A8h]

Read Slope [A9h]

Start Convert T [EEh]

This command begins a temperature conversion. No further data is required. In one-shot mode the

temperature conversion will be performed and then the DS1621 will remain idle. In continuous mode this

command will initiate continuous conversions.

Stop Convert T [22h]

This command stops temperature conversion. No further data is required. This command may be used to

halt a DS1621 in continuous conversion mode. After issuing this command, the current temperature

measurement will be completed and the DS1621 will remain idle until a Start Convert T is issued to

resume continuous operation.